Spark plug



Oct. 18,1927 1,646,318

E. A. SCHNEIDER ET AL SPARK PLUG Filed oct. 27, 1926 INVENTORS A'rrorNEYs Patented Oct. 18, 1927.

i UNITE STATES .PAT

ENT OFFICE.

EDWARD ALBERTQSCHNEIDRR, oF NEW YORK, N. Y.,*N:o MORRIS HERTZ, or

' STANFORD, CONNECTICUT. 'Y

SPARK PLUG.

Application filed ctober 27, 1926. Serial No. 144,568.

' This invention relates to spark plugs used in ignition systemsv of internal combustion engines. Y

. More particularly, the invention relates to spark plugs of the self-.cleaning type.

Sonie of the objects of the present inventions are to providel a spark plug of the indicated character with an electrode having an increased spark producing surface, so as to render the spark plug more reliable in operation; to pro-vide novel features of construction whereby carbon accumulations may be removed from the sparking surfaces to insu-re the desired spark at all times; to provide novel features of construction whereby any accumulation of carbon or oil will be au` vtomatically removed from the entire exposed surface of the core insulator after each explosion; to provide novel features of construction ina self-cleaning spark plug `which will prevent leakage andtherefore loss of power when the spark plug is in use; and to provide a self-'cleaning spark plugwhich may be manipulated:mechanically to remove deposits of carbon.

VThe nature of the invention and its distinguishing features and advantages will appear when the following specification is read in connection with the accompanying drawing, in which:

Figure 1 is a sectional elevation of the spark plug embodying the present invention; the insulator core and its electrode and sparking means being shown in a normal position. y

Figure 2 is .a view ofthe plug similar to that shown in Figure 1, but showingthe movable parts in the other extreme position.

Figure 3 is an elevation of the lower end of the spark plug.

Referring now morev particularly to the several views of the drawing, it will be apparent that, the spark plug, includes a metallic shell 10 having external threads for effecting the attachment of the plug which is a common feature. The shell 10 embodies a groundelectrode which would occur at 11. The shell 10 also has .a central cylindrical bore 12 which opens into an enlarged circular bore or recess 13, providing a shoulder 14. The bore orprecess 13 opens into a larger threaded bore 15, providing a shoulder 16. Extending through the shell 10V is van insulator core 17 which may be of any preferredvr construction, and is preferably made of porcelain, and` hasa collar 18, substantially midway 'of its length. Extending through the core 17', central thereof, is an electrical conductor or electrode 19. The upper end of the i electrode 19 has a cap 20 of conducting material and is pressed in contact with the upper tapered portion of the core 17 asl at 21. The

.cap 20has .a threaded member 22 on which is arranged for threading action, a binding nut 23. The upperA extremity ofthe electrode 19 is formed with a head 24 which preshoulder 14 the lower end of the core 17 will be some distance below the lower edge of the ground electrode-11. Thelower end of the electrode 19 has a disk 25 of conducting materialand is substantially equal in diameter to Vthe diameter of the lower end of the core 17. The said disk 25 is shown integral with the` electrode 19, but maybe made detachable. The disk 25 lies against the end of the core 17. A clamping nut 26 is employed. The nut 26 is externally threaded so as to' fit the threaded bore 15. The nut 26 also has a threaded bore 27. A gasket 28 of any kind, such as copper and asbestos is positioned on the shoulder 16. The clamping nut 26 is screwed down so as to tightly hold the gasket 28 in place on the shoulder 16 to prevent leakage at this point. A compression nut 29 is employed. The body of theV nut 29 is threaded so as to fit they bore 27 of the nut 26 whereby the nut 29 will be adjustable with respect to the nut 26. The nut 29 has a central bore 30 slightly larger in diameter than the diameter of the core 17, and said bore 30 opens int-o a larger bore vvents the nut 23 from working ofi' the Inem- 31 which provides a shoulder 32. It will be apparent that both nuts 26 and 29 surround the section of the core 17 above the collar 18. A compression spring 33 is employed.

The spring 33 surrounds the core 17 and is 11o y l portionsof the ground electrode 1`1 and disky 25. The force of the explosionin the engine cylinder, forces the core 17 upwardly against the action of the spring 33, and as a consequence the lower extremity ofthe core 17 `and the circumferential edge of the disk 25 is wiped clean of any carbon which may have been deposited bythe burned gases `in the` cylinder during the explosion. The lower portion of the core 17A and the disk 25 moves in contact with the wall of the bore 12 as shown in Figure 2.` lVlien the pressure inn the cylinder is relieved, the spring-33 returns the core 17 and therefore the disk A25 to a n0r- Vrnal relationship with respect to the shell 1() and therefore the ground electrode 11`.` i p vFrein the foregoing it will beobvious that increased sparking surfaces areprovided; that the vsparking surfaces and the entire portion of the core insulator, that is exposed to `the burningrgases inthe cylinder during the explosion," areat all times protected from any accumulation ofcarbon or oil; that the sparking surfaces areA at all times protected from any accumulation of carbon; that loss of power asthe 'result'of the loss of compression due `to leakage" through the plug is prevented; and thatithev resistance ofthe core to the action ofpresi sure applied theretoimay be varied.

` I claim:

1. spark plug comprising ametallic shell which provides a ground electrode and fa shoulder; an insulator core: extending through said shell, said core having a collar, an electrode` extending through said core, a disk of conducting material on "thelwer end of said electrode extending through the core, a clamping nut adjustably associated with said shell, a compression nut adjustably associated witlrsaid clamping nut, and a `spring between the collar on the core and the compression nut, `the collai` .engageable Iwith the .shoulder of `the shell to limit the downward movement of the core, said spring `allowing said core to move upwardly so that the `circumferential edge of the disk will niove in contact with fa portion of said 4shell and thus be wiped clean.

2. In a spark plug, `a shell, providing a ground electrode, said shell having a central bore, 'anfinsulatorcore arranged in said bore, said core being equal inidiameter to the dialnet-er ofsaid bore; a portion offsaid core normally extending belowV the lower `face of said ground electrode, an electrode 1 at theilower Vextremity of the core, saiddast f `electrode equalin diameter to the `diameter ofsaid bore; andimeans acting on the core wherebyfto allow the core to movenpwardly under the force` of explosion sothat the lower `portion of the` core and the f-electrode it carriedthereby will be cleaned by the :Wall ofthe, bore of any carbon depositedzthereon,

and said means-automatically foperable to return thecore lto its normalpositwn.

EDWARD ALBERT SCHNEIDER,`

`-MoneisHan'rz. 

